Call your credit card and have them force a refund, as you bought a ticket but will not be able to use it for travel. Then, buy it with your real credit card.
You can print out the receipt of your E-Ticket that was sent to you by email and present it at the Check-In counter in addition to your Passport. This is a valid procedure as per the airline’s website.
You should carry your traditional paper ticket or Itinerary Receipt
(or E-ticket) at all times for both international and domestic
flights.
How do I use my e-tickets? Present your printed e-tickets at Check in
Lao Airlines Counter at airport for each flight.
That being said – the reason the airline requires you to present the credit card is an additional safety measure to ensure you are the rightful owner of it.
Since the name on the credit card is your own you can proove ownership of this card by presenting your passport and there is no reason not to accept you for travel, unless the airline has a written policy that denies electronic credit cards. Even in this unlikely case though they would have to accept you for travel because it is not your fault if their payment system accepts a form of payment that goes against airline policy.
In sum: The airline has accepted your payment, which makes it valid. Print out your confirmation email with the E-Ticket no. on it and present it during Check-In along with your passport and you are good to go. Safe travels!
Credit:stackoverflow.com‘